Bug 1083587 - Add host and olderShadowRoot properties to ShadowRoot interface. r=smaug

content/base/src/FragmentOrElement.cpp

@@ -2954,6 +2954,6 @@ FragmentOrElement::SetIsElementInStyleScopeFlagOnShadowTree(bool aInStyleScope)
   ShadowRoot* shadowRoot = GetShadowRoot();
   while (shadowRoot) {
     shadowRoot->SetIsElementInStyleScopeFlagOnSubtree(aInStyleScope);
-    shadowRoot = shadowRoot->GetOlderShadow();
+    shadowRoot = shadowRoot->GetOlderShadowRoot();
   }
 }

content/base/src/ShadowRoot.cpp

@@ -481,6 +481,16 @@ ShadowRoot::SetInnerHTML(const nsAString& aInnerHTML, ErrorResult& aError)
   SetInnerHTMLInternal(aInnerHTML, aError);
 }
 
+Element*
+ShadowRoot::Host()
+{
+  nsIContent* host = GetHost();
+  MOZ_ASSERT(host && host->IsElement(),
+             "ShadowRoot host should always be an element, "
+             "how else did we create this ShadowRoot?");
+  return host->AsElement();
+}
+
 bool
 ShadowRoot::ApplyAuthorStyles()
 {

content/base/src/ShadowRoot.h

@@ -93,8 +93,7 @@ public:
   void RemoveInsertionPoint(HTMLContentElement* aInsertionPoint);
 
   void SetYoungerShadow(ShadowRoot* aYoungerShadow);
-  ShadowRoot* GetOlderShadow() { return mOlderShadow; }
-  ShadowRoot* GetYoungerShadow() { return mYoungerShadow; }
+  ShadowRoot* GetYoungerShadowRoot() { return mYoungerShadow; }
   void SetInsertionPointChanged() { mInsertionPointChanged = true; }
 
   void SetAssociatedBinding(nsXBLBinding* aBinding) { mAssociatedBinding = aBinding; }
@@ -125,6 +124,8 @@ public:
     GetElementsByClassName(const nsAString& aClasses);
   void GetInnerHTML(nsAString& aInnerHTML);
   void SetInnerHTML(const nsAString& aInnerHTML, ErrorResult& aError);
+  Element* Host();
+  ShadowRoot* GetOlderShadowRoot() { return mOlderShadow; }
   void StyleSheetChanged();
 protected:
   virtual ~ShadowRoot();

content/base/src/nsContentUtils.cpp

@@ -6816,7 +6816,7 @@ nsContentUtils::HasDistributedChildren(nsIContent* aContent)
   if (shadow) {
     // Children of a shadow root are distributed to
     // the shadow insertion point of the younger shadow root.
-    return shadow->GetYoungerShadow();
+    return shadow->GetYoungerShadowRoot();
   }
 
   HTMLShadowElement* shadowEl = HTMLShadowElement::FromContent(aContent);

content/html/content/src/HTMLShadowElement.cpp

@@ -144,7 +144,7 @@ HTMLShadowElement::BindToTree(nsIDocument* aDocument,
 
   if (mIsInsertionPoint && containingShadow) {
     // Propagate BindToTree calls to projected shadow root children.
-    ShadowRoot* projectedShadow = containingShadow->GetOlderShadow();
+    ShadowRoot* projectedShadow = containingShadow->GetOlderShadowRoot();
     if (projectedShadow) {
       for (nsIContent* child = projectedShadow->GetFirstChild(); child;
            child = child->GetNextSibling()) {
@@ -167,7 +167,7 @@ HTMLShadowElement::UnbindFromTree(bool aDeep, bool aNullParent)
   if (mIsInsertionPoint && oldContainingShadow) {
     // Propagate UnbindFromTree call to previous projected shadow
     // root children.
-    ShadowRoot* projectedShadow = oldContainingShadow->GetOlderShadow();
+    ShadowRoot* projectedShadow = oldContainingShadow->GetOlderShadowRoot();
     if (projectedShadow) {
       for (nsIContent* child = projectedShadow->GetFirstChild(); child;
            child = child->GetNextSibling()) {
@@ -220,7 +220,7 @@ HTMLShadowElement::DistributeSingleNode(nsIContent* aContent)
   // Handle the case where the parent of this shadow element is a ShadowRoot
   // that is projected into a shadow insertion point in the younger ShadowRoot.
   ShadowRoot* containingShadow = GetContainingShadow();
-  ShadowRoot* youngerShadow = containingShadow->GetYoungerShadow();
+  ShadowRoot* youngerShadow = containingShadow->GetYoungerShadowRoot();
   if (youngerShadow && GetParent() == containingShadow) {
     HTMLShadowElement* youngerShadowElement = youngerShadow->GetShadowElement();
     if (youngerShadowElement) {
@@ -247,7 +247,7 @@ HTMLShadowElement::RemoveDistributedNode(nsIContent* aContent)
   // Handle the case where the parent of this shadow element is a ShadowRoot
   // that is projected into a shadow insertion point in the younger ShadowRoot.
   ShadowRoot* containingShadow = GetContainingShadow();
-  ShadowRoot* youngerShadow = containingShadow->GetYoungerShadow();
+  ShadowRoot* youngerShadow = containingShadow->GetYoungerShadowRoot();
   if (youngerShadow && GetParent() == containingShadow) {
     HTMLShadowElement* youngerShadowElement = youngerShadow->GetShadowElement();
     if (youngerShadowElement) {
@@ -263,7 +263,7 @@ HTMLShadowElement::DistributeAllNodes()
   // into this shadow insertion point so update the destination insertion
   // points.
   ShadowRoot* containingShadow = GetContainingShadow();
-  ShadowRoot* olderShadow = containingShadow->GetOlderShadow();
+  ShadowRoot* olderShadow = containingShadow->GetOlderShadowRoot();
   if (olderShadow) {
     ExplicitChildIterator childIterator(olderShadow);
     for (nsIContent* content = childIterator.GetNextChild();
@@ -286,7 +286,7 @@ HTMLShadowElement::DistributeAllNodes()
 
   // Handle the case where the parent of this shadow element is a ShadowRoot
   // that is projected into a shadow insertion point in the younger ShadowRoot.
-  ShadowRoot* youngerShadow = containingShadow->GetYoungerShadow();
+  ShadowRoot* youngerShadow = containingShadow->GetYoungerShadowRoot();
   if (youngerShadow && GetParent() == containingShadow) {
     HTMLShadowElement* youngerShadowElement = youngerShadow->GetShadowElement();
     if (youngerShadowElement) {

dom/tests/mochitest/webcomponents/mochitest.ini

@@ -24,7 +24,9 @@ support-files =
 [test_template_xhtml.html]
 [test_shadowroot.html]
 [test_shadowroot_inert_element.html]
+[test_shadowroot_host.html]
 [test_shadowroot_style.html]
 [test_shadowroot_style_multiple_shadow.html]
 [test_shadowroot_style_order.html]
+[test_shadowroot_youngershadowroot.html]
 [test_style_fallback_content.html]

dom/tests/mochitest/webcomponents/test_shadowroot_host.html

@@ -0,0 +1,41 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1083587
+-->
+<head>
+  <meta charset="utf-8">
+  <title>Test for Bug 1083587</title>
+  <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1083587">Mozilla Bug 1083587</a>
+<p id="display"></p>
+<div id="content" style="display: none">
+<div id="host"></div>
+</div>
+<pre id="test">
+</pre>
+<script type="application/javascript">
+
+/** Test for Bug 1083587 **/
+var hostInDoc = document.getElementById("host");
+var shadowOne = hostInDoc.createShadowRoot();
+is(shadowOne.host, hostInDoc);
+
+var shadowTwo = hostInDoc.createShadowRoot();
+is(shadowOne.host, hostInDoc);
+is(shadowTwo.host, hostInDoc);
+
+var hostNotInDoc = document.createElement("div");
+var shadowThree = hostNotInDoc.createShadowRoot();
+is(shadowThree.host, hostNotInDoc);
+
+var shadowFour = hostNotInDoc.createShadowRoot();
+is(shadowThree.host, hostNotInDoc);
+is(shadowFour.host, hostNotInDoc);
+
+</script>
+</body>
+</html>

dom/tests/mochitest/webcomponents/test_shadowroot_youngershadowroot.html

@@ -0,0 +1,41 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1083587
+-->
+<head>
+  <meta charset="utf-8">
+  <title>Test for Bug 1083587</title>
+  <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1083587">Mozilla Bug 1083587</a>
+<p id="display"></p>
+<div id="content" style="display: none">
+<div id="host"></div>
+</div>
+<pre id="test">
+</pre>
+<script type="application/javascript">
+
+/** Test for Bug 1083587 **/
+var hostInDoc = document.getElementById("host");
+var shadowOne = hostInDoc.createShadowRoot();
+is(shadowOne.olderShadowRoot, null);
+
+var shadowTwo = hostInDoc.createShadowRoot();
+is(shadowOne.olderShadowRoot, null);
+is(shadowTwo.olderShadowRoot, shadowOne);
+
+var hostNotInDoc = document.createElement("div");
+var shadowThree = hostNotInDoc.createShadowRoot();
+is(shadowThree.olderShadowRoot, null);
+
+var shadowFour = hostNotInDoc.createShadowRoot();
+is(shadowThree.olderShadowRoot, null);
+is(shadowFour.olderShadowRoot, shadowThree);
+
+</script>
+</body>
+</html>

dom/webidl/ShadowRoot.webidl

@@ -19,6 +19,8 @@ interface ShadowRoot : DocumentFragment
   HTMLCollection getElementsByClassName(DOMString classNames);
   [SetterThrows,TreatNullAs=EmptyString]
   attribute DOMString innerHTML;
+  readonly attribute Element host;
+  readonly attribute ShadowRoot? olderShadowRoot;
   attribute boolean applyAuthorStyles;
   readonly attribute StyleSheetList styleSheets;
 };

testing/web-platform/meta/shadow-dom/elements-and-dom-objects/shadowroot-object/shadowroot-attributes/test-014.html.ini

@@ -1,5 +0,0 @@
-[test-014.html]
-  type: testharness
-  [ShadowRoot.olderShadowRoot_T01]
-    expected: FAIL
-